People are advised not to go swimming or fishing at McLaren Falls this long weekend, with water quality tests this week revealing unsafe levels of bacteria.

Bay of Plenty Regional Council has extended its current water safety alerts to include the Wairoa River at McLaren Falls and Bethlehem, Kaiate Falls, and the Kopurererua Stream.

People are being advised not to swim or fish in the Wairoa River at McLaren Falls.

People are asked not to swim or fish at the above locations until further notice.

Regional Council Water scientist Paul Scholes says because of the weather, many stormwater drains and ponds had had little or no flow leaving the water at risk of bacterial contamination.

'The water is sitting stagnant, and the high temperatures we've been having increases bacteria and a build-up of other contaminants which could be a health risk to both people and pets.”

Water at Harrisons Cut outfall onto Papamoa Beach, where families often swim and paddle, is being regularly monitored for health risks. Tauranga City Council has deepened the channel across the beach to allow better tidal flow up the drain to improve water flows.

Paul says people should not swim or paddle there.

'Stormwater may look clean, but it has washed off roofs and roads, and may be contaminated by ducks and other avian species. Swimming or paddling in stormwater ponds or near stormwater pipe outlets could make you sick.

'Pets should also be kept out of stormwater ponds and drains, as they too can be affected by water-borne bacteria."

Low flows and hot summer weather could also affect water quality in popular swimming spots.

The Regional Council monitors swimming water quality more than 80 popular coastal, river and lake recreation sites around the Bay of Plenty for bacteria and for toxin-forming algae